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Angle of Torsion.

Moment of shaft=moment of key (bearing)=moment of key (shearing)

. hid                          , ,d

(3)

(I)

442

Then by (5) h = '75 *'

By (3) and (i)    ^x-i963^=^
4                   4

By (i) and (2)

Let b = -3 t
By (4)   ^/=*2944^2        and l=r$d

In practice the following rules are adopted :
b = j d -f- ^r" and /^ =

Then /. '2944^

.-. >%/=-2944^2    (4)
 *-|^.........(5)

Angle of Torsion, or the angle through which one end of
a shaft turns relatively to the other under a given stress.

'Ibs

p _ shear stress __/slbs
shear strain      6S

Referring to Fig. 376 and putting 6 in circular measure (viz. ? )

\      rad. /

^s                                                                   *         /lbs

8 =  for every inch of shaft length.    Substituting y-~- for bs

9total=-gx/

If a weight a/ produce a twist 0 (Fig. 377), then
utwr2=fs s_